lost iscsi storage lun

[Matthew_Shuter]

Dell PowerEdge 6850 running ESX 3.5, with qlogic 4052 hba, connected to HP ProCurve switch

Dell/EMC AX150i

virtual disk 1, just less than 2TB in size, assigned to the server

RDM direct map to Windows 2003 guest, formatted as ntfs

the rdm drive is no longer available to the guest.

when I look at the host ESX server, it still sees the LUN under storage adapters. ity is not there under storage, although another lun from the same ax150i is, which is holding ISOs for the server. If I go to add storage, the LUN is available to add, but it wants to possibly format it, and I would lose all of the data, which I dont want to do.

any thoughts on what I should do/try?

one thought would be to present the LUN to another server, either another ESX host or physical windows box. I have two other ESX hosts that I can use, but would have to setup a physical windows box to our iscsi network.

Thanks for any advice.

Matt Shuter

[ctfoster]

Well the first thing - you are right in avoiding the 'Add Storage' option unless you've got some very good backups!

Take a look at the /var/log/vmkernel file to see if there are any errors relating to this LUN - particularly those making any mentions of snapshots.

[Matthew_Shuter]

my guess this line in the log is telling me I am screwed:

WARNING: SCSI: 2252: The physical media represented by vmhba6:0:0 has changed. The device cannot be re-synchronized with the system. This is a critical error.

looking through the logs some more, but nothing jumping out at me.

[kjb007]

Remove the RDM definition from the vm, and re-create it. As long as you remove the drive, but leave the file in tact, you should be able to re-add it again, as long as y ou haven't deleted or formatted anything.

-KjB

[Plunket]

We are about to upgrade our 3.0.1 ESX servers to 3.5 and this is what worrying me as well. Rejoin the iSCSI will format the disk.

Can you tell me more detail of how to remove RDM in VM and reconnect the storage again without format it?

Thanks

[kjb007 · Accepted solution]

An RDM is configured at the VM level. Edit the settings for the vm, and remove the disk that is an RDM. When you remove, it will ask if you only want to remove the config, or delete the files, make sure you DO NOT select remove files. Once that is done, go through the wizard to add the RDM, and select the LUN you just "released".

-KjB

[Matthew_Shuter]

I didn't have to do anything special when I upgraded this box from ESX 3.0.2 to 3.5. I did that a little while ago, and this apparently was something unrelated.

[Matthew_Shuter]

KjB,

thanks, that worked perfectly. When I tried to remove the drive, it errored out about an incorrect parameter. When I went back into settings, it was there. This is my opnly RDM, so I forgot how it was setup originally... now it makes sense that I don't see it under storage. Thanks again.

matt

[kjb007]

No problem. Glad it all worked out.

-KjB